Objective: To analyze the role that low income plays in the development of asthma in children and adolescents. Methods: A case-control study using a questionnaire. Results: A total of 687 participants were studied at a tertiary hospital via the Brazilian Unified Health System. Ages ranged from 5 to 15 years, and 54.7% of the participants were male. Nearly half of the individuals (49.1%) lived in the metropolitan area of the city of Recife, and the remainder lived in the countryside. Most (98.1%) lived in concrete houses or apartments, with a mean of 5.7 rooms and 4.8 occupants per residence. Mean maternal level of education was 6.8 years of schooling. The median monthly per capita income was R$ 103.75 (Brazilian reals). The sample was stratified according to cut-off points related to the national minimum wage (R$ 350.00): <25% of minimum wage = very low income (39% of the sample); <50% of minimum wage = low income (37.3% of the sample); and ≥50% of minimum wage = satisfactory income (23.7% of the sample). There was no association between poverty and development of asthma. Conclusions: Poverty is not protective against asthma in children and adolescents treated via the Brazilian Unified Health System, as we might suppose based on the hygiene hypothesis. However, cohort studies are needed in order to confirm these findings.

Keywords: Asthma; Poverty; National health programs/Brazil; Child; Adolescent; Case-control studies.

Objective: To evaluate post-operative complications in living lobar lung transplant donors. Methods: Between September of 1999 and May of 2005, lobectomies were performed in 32 healthy lung transplant donors for 16 recipients. The medical charts of these donors were retrospectively analyzed in order to determine the incidence of post-operative complications and alterations in pulmonary function after lobectomy. Results: Twenty-two donors (68.75%) presented no complications. Among the 10 donors presenting complications, the most frequently observed complication was pleural effusion, which occurred in 5 donors (15.6% of the sample). Red blood cell transfusion was necessary in 3 donors (9.3%), and 2 donors underwent a second surgical procedure due to hemothorax. One donor presented pneumothorax after chest tube removal, and one developed respiratory infection. There were two intra-operative complications (6.25%): one donor required bronchoplasty of the middle lobe; and another required lingular resection. No intra-operative mortality was observed. Post-operative pulmonary function tests demonstrated an average reduction of 20% in forced expiratory volume in one second (p < 000.1) compared to pre-operative values. Conclusions: Lobectomy in living lung transplant donors presents high risk of post-operative complications and irreversible impairment of pulmonary function. Careful pre-operative evaluation is necessary in order to reduce the incidence of complications in living lobar lung transplant donors.

Keywords: Lung transplantation; Living donors; Pneumonectomy; Postoperative complications.

Objective: To correlate tomographic findings with pulmonary function findings, as well as to compare chest X-ray findings with high-resolution computed tomography (HRCT) findings, in patients with silicosis. Methods: A cross-sectional study was conducted in 44 non-smoking patients without a history of tuberculosis. Chest X-ray findings were classified according to the International Labour Organization recommendations. Using a semiquantitative system, the following HRCT findings were measured: the full extent of pulmonary involvement; parenchymal opacities; and emphysema. Spirometry and forced oscillation were performed. Pulmonary volumes were evaluated using the helium dilution method, and diffusing capacity of the lung for carbon monoxide was assessed. Results: Of the 44 patients studied, 41 were male. The mean age was 48.4 years. There were 4 patients who were classified as category 0 based on X-ray findings and as category 1 based on HRCT findings. Using HRCT scans, we identified progressive massive fibrosis in 33 patients, compared with only 23 patients when X-rays were used. Opacity score was found to correlate most closely with airflow, DLCO and compliance. Emphysema score correlated inversely with volume, DLCO and airflow. In this sample of patients presenting a predominance of large opacities (75% of the individuals), the deterioration of pulmonary function was associated with the extent of structural changes. Conclusions: In the early detection of silicosis and the identification of progressive massive fibrosis, HRCT scans are superior to X-rays.

Keywords: Silicosis; Occupational diseases; Tomography, x-ray computed; Respiratory function tests.

Objective: To evaluate the effects of azathioprine on the mucociliary system in a model of bronchial section and anastomosis in rats. Methods: Thirty-six male Wistar-Furth rats were submitted to left bronchial section and anastomosis and divided into two groups to receive either saline solution or azathioprine. After 7, 15 and 30 days of treatment, six animals from each group were killed, after which in situ mucociliary transport velocity, in vitro mucus transportability, and contact angle of mucus in the right (intact) and left (sectioned) bronchi were measured. Results: In situ mucociliary transport velocity was significantly lower in the sectioned bronchi than in the intact bronchi (p < 0.001). In situ mucociliary transport velocity was lower in the intact bronchi of the animals treated with azathioprine for 7 days (p < 0.05), and those bronchi presented full recovery after 30 days of treatment. The contact angle was higher in the mucus samples collected from the sectioned bronchi of the animals treated with saline solution for 30 days (p < 0.001), which is in accordance with the decreased in vitro mucus transportability observed in the same animals (p < 0.001). Conclusions: We conclude that, in the sectioned bronchi of rats, treatment with azathioprine causes only transitory impairment of mucociliary transport, whereas administration of saline solution impairs mucociliary transport for up to 30 days. In addition, azathioprine protects against alterations in mucus surface properties.

Keywords: Mucociliary clearance; Anastomosis, surgical; Immunosuppression; Lung.

Objective: To study correlations among pulmonary function, chest radiology and clinical status in cystic fibrosis. Methods: A retrospective cross-sectional study was performed to evaluate chest X-rays and clinical charts of patients treated at the Hospital de Clínicas de Porto Alegre. Spirometry findings, Shwachman-Kulczycki (S-K) scores and Brasfield scores were analyzed. Results: The final sample consisted of 40 patients (mean age 9.72 ± 3.27). The following mean S-K scores were obtained: total, 80.87 ± 10.24; general activity, 24.75 ± 1.1; physical examination, 18.87 ± 4.59; nutrition, 21.87 ± 4.18; radiology, 15.37 ± 5.23. The mean Brasfield score was 18.2 ± 4. The pulmonary function test results, in percentage of predicted, were as follows: forced vital capacity (FVC), 82.99 ± 14.36%; forced expiratory volume in one second (FEV1), 83.62 ± 18.26%; and forced expiratory flow between 25 and 75% of FVC (FEF25-75), 74.63 ± 2.53%. The S-K score correlated moderately with FVC, whereas it correlated strongly with FEV1 and FEF25-75. The Brasfield score correlated strongly with the S-K total and radiology score, whereas it correlated moderately with pulmonary function. Physical examination correlated moderately with FVC, FEV1 and FEF25-75; as did nutrition with FEF25-75; and radiology with FEV1 and FEF25-75. General activity was the domain that had the greatest influence on the total S-K score. Conclusions: These two scoring systems are complementary, correlating with each other, as well as with pulmonary function tests. The radiology domain of the S-K scoring system is a good alternative to the Brasfield score.

Keywords: Cystic fibrosis; Spirometry; Lung/radiography.

Objective: To determine the prevalence of smoking among dentists in the Federal District of Brasília, Brazil. Methods: A descriptive, cross-sectional survey, involving 446 dentists residing in the Federal District, was conducted in the second semester of 2004. Data regarding the smoking habit were obtained using a World Health Organization questionnaire that was translated and validated for use in Brazil by the Brazilian National Cancer Institute. Individuals who had smoked a minimum of one cigarette per day for at least 6 months prior to the study outset were classified as regular smokers. The distribution of frequencies was analyzed using descriptive statistics (means and standard deviations), as well as calculation of prevalence rates. The different variables were compared using the chi-square test, and values of p < 0.05 were considered statistically significant. Results: Of the dentists evaluated, 37% (42% of the males and 31.4% of the females) reported being smokers. Conclusions: The prevalence of smokers among dentists in the Federal District is above the national average for the adult population, which is approximately 32%. Although there was a predominance of males, the high number of female dentists who reported being smokers was a worrisome finding.

Keywords: Dentists; Smoking; Prevalence.

Objective: The purpose of this study was to investigate endotracheal tube cuff pressure (Pcuff) alteration in patients under mechanical ventilation after changes in position. Methods: All selected patients were initially placed in the 35° semi-Fowler position, with Pcuff adjusted to 20 mmHg, and randomly divided into two groups. Group A, in which patients were moved to the lateral decubitus position, facing away from the ventilator (measurement designated Pcuff A1), returned to the initial position (measurement designated Pcuff A2), moved to a lateral decubitus position, facing the ventilator (measurement designated Pcuff A3) and then returned to the initial position (measurement designated Pcuff A4); and Group B, in which patients were moved to the lateral decubitus position, facing the ventilator (measurement designated Pcuff B1), returned to the initial position (measurement designated Pcuff B2), moved to the lateral decubitus position; facing away from the ventilator (measurement designated Pcuff B3) and then returned to the initial position (measurement designated Pcuff B4). Results: The study comprised 70 patients, 31 allocated to group A and 39 allocated to group B. Values >22 mmHg were observed in 142(50.7%) of the 280 Pcuff measurements taken, and values <18 mmHg were observed in 14 (5%). When moved from the 35° semi-Fowler position to the lateral decubitus position, facing away from the ventilator, 58 (82.2%) of the patients presented mean Pcuff values in the higher range (>22 mmHg). Conclusions: Changes in body position can cause significant Pcuff variations in patients under mechanical ventilation.

Keywords: Pressure; Intubation, intratracheal; Posture; Supine position.

Objective: To evaluate surveillance of contacts of new tuberculosis cases in the state of Mato Grosso from 1999 to 2004. Methods: This was a descriptive epidemiological study based on data from the Tuberculosis Case Registry Database. The number of new tuberculosis cases, the number of contacts (estimated, investigated, and uninvestigated), and the tuberculosis incidence rate were analyzed by age bracket. The mean rate of contacts investigated for each case of tuberculosis by age bracket was calculated per year of study. The cases of pulmonary tuberculosis with and without contacts investigated were analyzed by sputum smear microscopy results. Results: In 2004, there were 41.3 cases of tuberculosis per 100,000 inhabitants in the state of Mato Grosso. The south-central region presented the highest incidence rate (57 cases/100,000 inhabitants) and a 15% rate of contacts investigated. Among those younger than 15 years, 63 contacts (60.5%) were investigated, whereas among those aged 15 or older, 389 (8.9%) were investigated. In 1999, the mean rate of contacts investigated statewide was 0.02 (0.5%), and, in 2004, it reached 0.42 (10.5%). The percentage of contacts investigated was 40% higher among the contacts of contagious cases (OR = 1.4; 95% CI: 1.08-1.83). Conclusions: The percentage of contacts investigated is very low, principally among adults. The adoption of the standards for investigation of tuberculosis contacts proposed by the Brazilian National Ministry of Health Department of Health Surveillance has not ensured that this group at highest risk of developing active tuberculosis be given priority at health care facilities in the state of Mato Grosso.

Keywords: Contact tracing; Epidemiologic surveillance; Tuberculosis/prevention & control.

Objective: To propose a methodology for characterizing proficiency in sputum smear microscopy for acid-fast bacilli (AFB) in the diagnosis of tuberculosis and to determine the number of microscopies necessary to establish this proficiency, as well as the quality of the transcription of results, the causes of the discrepancies in the readings (rater or microscope used), and the criterion for classification of microscopy results that poses the most difficulty in characterizing proficiency. Methods: Four hundred sputum smear microscopies for the diagnosis of tuberculosis were analyzed through double-blind readings by six professionals who usually read/supervise microscopies performed in public health care facilities. The sample was stratified to obtain, at least, a reliability of 90% in the double-blind readings, an α error of 5%, and a precision of 3%. The results were analyzed using observed reliability and the kappa index. Results: Thirteen errors (0.27%) were found in the transcription of results. Reliability increased when the three distinct categories of positive results (AFB+, AFB++, and AFB+++) were grouped or when inconclusive results were excluded from the analysis. The quantification of the bacterial load was the classification criterion that posed the most difficulty in establishing proficiency. Using higher quality microscopes increased reliability. Reliability values stabilized only from the reading of 75 microscopies onward. Conclusions: Double-blind sputum smear microscopy readings using a panel containing 75 slides (36 negative, 4 inconclusive, and 35 positive) proved to be appropriate for characterizing proficiency in sputum smear microscopy for the diagnosis of tuberculosis when such proficiency is intended to reproduce laboratory routine.

Keywords: Tuberculosis; Microscopy; Reproducibility of results.

The relationship between cancer and coagulopathy was suggested by Trousseau nearly 150 years ago. Later, it became more evident that oncologic patients are at a higher risk of experiencing thromboembolic events. This can be due to activation of the coagulation system either by neoplastic cells or by prescribed therapies (chemotherapy or surgical procedures). In fact, these events can constitute the first manifestation of cancer, and their recurrence, despite efficient anticoagulation, has been described. The coagulation system is normally activated in order to provide healing. In the presence of neoplasms, this complex system is activated as a response to multiple stimuli and seems to contribute to cancer progression. Activation of the coagulation system has a greater effect on metastatic foci than on the primary tumor. However, most cancer victims die from complications caused by metastasis, which underscores the importance of this theme. In this area, various mechanisms have been described, creating promising perspectives for future treatments. The current success in using low-molecular-weight heparins against small cell lung cancer is encouraging. Although the knowledge of those mechanisms is relatively incipient, many basic research and clinical studies are underway.

Keywords: Lung neoplasms; Thrombophilia.

Here, we report high-resolution computed tomography (HRCT) findings in a patient who developed sudden hemoptysis, dyspnea and chest pain after smoking crack cocaine. Chest X-rays showed consolidations, primarily in the upper lobes, and HRCT scans showed ground glass attenuation opacities, consolidations and air-space nodules. A follow-up CT, after drug use discontinuation and administration of corticosteroids, showed partial resolution of pulmonary lesions and the appearance of cavitations. Clinical, imaging and laboratory findings led to a diagnosis of 'crack lung'.

Keywords: Crack cocaine/adverse effects; Cocaine-related disorders; Tomography, X-ray computed; Street drugs/adverse effects;

Pulmonary thromboembolism is a common condition. Its diagnosis usually requires pulmonary scintigraphy, computed angiotomography, pulmonary arteriography and, in order to rule out other diagnoses, the measurement of D-dimer levels. Due to the fact that these diagnostic methods are not available in most Brazilian hospitals, the validation of other diagnostic techniques is of fundamental importance. We describe a case of a woman with chronic pulmonary hypertension who experienced a pulmonary thromboembolism event. Pulmonary scintigraphy, computed angiotomography and pulmonary arteriography were used in the diagnosis. The D-dimer test result was positive. Volumetric capnography was performed at admission and after treatment. The values obtained were compared with the imaging test results.

Keywords: Thromboembolism; Hypertension, pulmonary; Capnography; Schistosomiasis.

The incidence of lung neoplasms is increasing in Brazil and in the world, probably as a result of the increase in smoking. Due to the greater number of cases, atypical presentations appear. We report the case of a 66-year-old hypertensive male smoker who presented progressive proximal muscular weakness and, in two months, evolved to dysphagia, dysphonia, and V-shaped skin lesions on the chest. A chest X-ray showed a spiculated pulmonary nodule in the right upper lobe. The biochemical analysis revealed elevated creatine kinase levels. After complementary tests and biopsies, the patient underwent right upper lobectomy. Histopathology showed a moderately differentiated adenocarcinoma. The overall analysis of the case and a review of the literature allow us to suggest that the clinical profile of the patient was a result of an overlap of two paraneoplastic syndromes (dermatomyositis and Lambert-Eaton myasthenic syndrome) secondary to lung adenocarcinoma.

Keywords: Lung neoplasms; Paraneoplastic syndromes; Dermatomyositis; Lambert-Eaton myasthenic syndrome; Adenocarcinoma.